<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div {
            position: absolute;
            top: 2px;
            width: 100px;
            height: 100px;
            background-color: pink;
        }
    </style>
</head>

<body>
    <div></div>
    <script>
        let div = document.querySelector('div');
        div.addEventListener('mousedown', function (e) {
            var mouseX = e.pageX - this.offsetLeft;
            var mouseY = e.pageY - this.offsetTop;
            div.addEventListener('mousemove', movefunc)
            function movefunc(e) {
                var boxX = e.pageX - mouseX;
                var boxY = e.pageY - mouseY;
                div.style.left = boxX + "px";
                div.style.top = boxY + "px";

            }
            div.addEventListener('mouseup', function () {
                div.removeEventListener('mousemove', movefunc)
            })
        })

    </script>
</body>

</html>